Windows XP TCPIP limit? 1

[tedsmith]

I notice the docs say that Windows XP can only handle 10 TCPIP connections at the one time with the latest Service Pack.
They also said this about Windows2000 but you can see hundreds of workstations on our LAN simply using Windows Explorer although you don't see some workstations that start up after the viewing computer has started.

I wrote a program that connects to 20 other computers using 20 Socketwrench sockets on our LAN and it works OK with a mix of Win2000 and Win98.

Has anyone had any problems with this on XP?

 

[Serbtastic]

You are confused. The 10 connection limit applies to INCOMING connections.

 

[tedsmith]

Thanks.
Does this mean I couldn't open more than 10 windows windows explorer windows and have more than 10 computers' folders all showing at the same time?

 

[globalchicken]

To me that means that if you were to use XP as a server, then only ten clients at one time could connect to those resources. The 11th one would be disconnected...
DOes that make sense?

 

[LawnBoy]

Does this mean I couldn't open more than 10 windows windows explorer windows and have more than 10 computers' folders all showing at the same time?

Nope, you've still got it backwards. If you share a folder, you can only have 10 people connected to your share. If you run a database, you can only have 10 people connected to the database.

I don't believe the restriction applies to a webserver (IIS, Apache, etc.)

 

[tedsmith]

Thank you LawnBoy but I am concerned that the XP limit of 10 now applies to simple sockets established to a number of computers. As I intrepret it, the latest info by Microsoft refers to a limit of 10 TCPIP connections that was introduced by the latest Service pack to help with internet security.
The program I made uses 20 sockets from one computer connected to 20 workstations. I use it to feed special instructions to these users in a small window on top of whatever they are doing.
I am worried that if all the computers on this LAN are upgraded to XP, my 20 connections will work or not.
Might I have to use a server version of XP if such a thing exists? The LAN is not connected to the web.
Have you any ideas on this?

 

[Serbtastic]

You will be able to initiate connections to 20 workstations just fine. Again, the limit is on INCOMING connections.

Also, there is no such thing as XP server, Windows 2003 server would be the one to use.

 

[tedsmith]

Thanks.
Interestingly enough, the way I connect to the 20 work stations is probably unusual.
They connect to me by first telling me their address in turn using port 7. Then I connect to them in turn using a different port for each workstation (1000 to 1020).
I suppose this in effect gets around the incoming limit and I don't even have to know in advance the work stations' addresses?

 

[Serbtastic]

Nope, you still have it wrong. The incoming connection limit would have nothing to do with how you initiate an outgoing connection to other machines.

 

[tedsmith]

I must be still missing something!

Do you mean that if the TCPIP connections are established by the server there is no limit but if the same connections were established by the workstations, there would be a limit?

My TCPIP connections are two way in that I use a socket at each end and can send and receive data both ways between the master (server) and each workstation (client)
This means that my master had 20 outputs and 20 inputs while each workstation has only one input and one output each.
I have Windows 2000 in every computer and the 20 connections remain intact continuously but data is only exchanged to one computer at a time.
How come this doesn't exceed the limit rule for the master server as it can connect, send and receive to 20 computers?

Does this 'limit' refer to communications that may be happening simultaneously or is there some other thing I have missed?

I am concerned whether my system will still work if I update all computers to XP!

 

[Zelandakh]

TCP connections are directional and only one way. You say your connections are 2 way but in fact what you have is 2 one way connections for data transmission.

A computer can initiate a TCP connection on port 21 (for instance) into a Windows XP box. Then another 9 computers can connect but not the 10th one until one of those connections is dropped or times out. You can check the status of these using netstat

Outbound connections FROM the Windows XP Pro box are in excess of 60,000 technically.

 

[tedsmith]

Thanks, Zelandakh. mmm, the plot thickens!
The 20 connections I have on my current Win2000 system remain connected even though the docs for Win2000 say it shouldnt.

However I am using a different port for each work station (ports 1000 to 1020)
The workstations are not accessing the same data file, they just get data sent to them and send an acknowledge back.
Do you think I could use have more than 10 connections if I used different ports?
Ted

 

[Serbtastic]

It has nothing to do with ports. The connection limit is 10 for connections initiated from another machine TO the Windows 2000 Pro / XP Pro machine.

 

[tedsmith]

Thank you Serbtastic.
Do you mean you can have up to 10 TCPIP connections between any two computers?

But, say you had 3 computers in a network, could you have 10 between A and B and 10 between B and C? This would mean that B had a total of 20 ports operating but not to the same computer?
In the documentation for the socket DLL, it says there is a limit of 64 different ports for any one computer. Can these actually be connected to 64 other computers in XP pro? I have tried it in Win2000 and it works with up to 64 ports.